Upper Ordovician strata exposed from the Baiyanhuashan section is the most representative Late Ordovician unit in the northwestern margin of the North China Craton (NCC). In total, 1,215 conodont specimens were obtained from 24 samples through the Wulanhudong and Baiyanhuashan formations at the Baiyanhuashan section. Thirty-six species belonging to 17 genera, including Tasmanognathus coronatus new species, are present. Based on this material, three conodont biozones—the Belodina confluens Biozone, the Yaoxianognathus neimengguensis Biozone, and the Yaoxianognathus yaoxianensis Biozone—have been documented, suggesting that the Baiyanhuashan conodont fauna has a stratigraphic range spanning the early to middle Katian. The Baiyanhuashan conodont fauna includes species both endemic to North China and widespread in tropical zones, allowing a reassessment of the previous correlations of the Katian conodont zonal successions proposed for North China with those established for shallow-water carbonate platforms at low latitudes.

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Although previous research has found that authentic leadership has a negative effect on employee burnout through structural empowerment, lack of psychological empowerment in the research cannot present a complete picture on how authentic leadership influences burnout because employees must experience being psychologically empowered for empowerment to be effective. Drawing on empowerment-related theories, this study integrates the three different perspectives of empowerment (authentic leadership, structural empowerment, and psychological empowerment) to examine their effects on emotional exhaustion, the core component of burnout, at multiple levels of analysis. Using a sample of 378 teachers from 59 primary and secondary schools in China, multilevel structural equation modelling results revealed that: (1) authentic leadership had an indirect effect on psychological empowerment partially through structural empowerment, (2) psychological empowerment played a full mediating role in the relationship between structural empowerment and emotional exhaustion, and (3) structural empowerment and psychological empowerment sequentially mediated the effect of authentic leadership on emotional exhaustion. Theoretical and practical implications are discussed.

A congruent melting compound LiNaV2O6 has been synthesized by high-temperature solution reaction and it has been grown with sizes up to 11 × 6 × 2 mm3 by the top-seeded growth method for the first time. LiNaV2O6 crystallizes in the monoclinic system with space group C2/c, with a = 10.184(2) Å, b = 9.067(2) Å, c = 5.8324(11) Å, β = 108.965(14)°. UV–Vis–NIR diffuse reflectance spectrum of LiNaV2O6 shows that it has a wide transmittance range from 385 to 2500 nm. The ab initio calculations show that the birefringence of LiNaV2O6 is 0.136 at 589.3 nm. Therefore, LiNaV2O6 may be a new birefringent material. Based on the analysis of the relationship between crystal structure and linear optical properties, it is found that the large birefringence is attributed to the particular arrangement of V–O anionic groups.

A noncentrosymmetric aluminum borate crystal, Al5BO9, was obtained via high-temperature solution method. Considering the structure diversities of Al5BO9, the single crystal structure was cautiously redetermined before the investigation. The fundamental building blocks of the structure are BO3 triangles, AlO4 tetrahedra, and AlO6 octahedra. Since Al5BO9 only consists of strong covalent B–O and Al–O bonds, it is worth investigating the structure–optical property relationship thoroughly, especially the linear and nonlinear optical properties. To gain further insight into the origin of the nonlinear optical response of Al5BO9, the electronic structure calculations, second harmonic generation (SHG)-weighted electron density, and dipole moment of polyhedra were analyzed in detail. All evidences deduced from calculated results indicate that the SHG contribution from the Al–O polyhedra is more pronounced than that of the BO3 group in Al5BO9, which is anticipated to open a window for the search and design of new inorganic materials.

An improved two-temperature model to describe femtosecond laser ablation of metal target was presented. The temperature-dependent heat capacity and thermal conductivity of the electron, as well as electron temperature-dependent absorption coefficient and absorptivity are all considered in this two-temperature model. The tailored two-temperature model is solved using a finite difference method for copper target. The time-dependence of lattice and electron temperature of the surface for different laser fluence are performed, respectively. The temperature distribution of the electron and lattice along with space and time for a certain laser fluence is also presented. Moreover, the variation of ablation rate per pulse with laser fluence is obtained. The satisfactory agreement between our numerical results and experimental data indicates that the temperature dependence of heat capacity, thermal conductivity, absorption coefficient and absorptivity in femtosecond laser ablation of metal target must not be neglected. The present model will be helpful for the further experimental investigation of application of the femtosecond laser.